We request funds to help defray the travel and lodging expenses of speakers and chairpersons who will participate in the Thirty-ninth Annual Symposium on Fundamental Cancer Research, sponsored by The University of Texas System Cancer Center, M.D. Anderson Hospital and Tumor Institute. The meeting will be held from February 25, 1986 through February 28, 1986, in Houston, Texas. The purposes of this Symposium are a) to stimulate discussion of recent advances in a particular area of basic research and their application to cancer prevention and treatment; b) to provide a forum for scientific exchange among basic researchers and clinical practitioners; and c) to provide an overview of recent advances in a particular area of cancer research. The topic of the 1986 Symposium is "Critical Molecular Determinants of Carcinogenesis." The mechanisms that influence the induction of cancer by chemical agents, is under intense examination by sophisticated molecular techniques. This vital study is aimed at identifying obligate interactions between activated metabolites and chemical components of the cells; the biologic alterations that result; modifying factors such as genetic predisposition, and where possible, techniques by which these sequences may be halted or reversed. The program of the symposium will communicate state-of-the-art advances in the mechanisms of related DNA alterations (mutations); molecular alterations associated with cellular promotion and progression; possible role of oncogenes in phases of this process; effects upon cell surfaces and cell to cell communication. The relationships between these processes and related biologic phenomena such as aging and embryonic development will be examined. Potential methods by which the progression may be halted, such as nutritional intervention, free-radical scavenging and others will be explored. We have begun to invite distinguished researchers and theoreticians to participate in these presentations and discussions.